The biggest thing the original Ion lacked was an easily-accessible bolt. Needed to be completely disassembled just to relube the bolt.
Shocktech body is semi-bob (bolt out back), meaning you need to remove the rear frame screw, slide off the backcap, then unscrew the firing can to reach the bolt. Still MUCH better than complete disassembly, though.
When i first assembled it, the back cap shredded the firing can's o-rings. Upon inspection, the inner edges of the airway in the backcap were pretty sharp and had some loose burrs. Removed those and sanded around the airway hole and that seems to have solved the shredding problem.
After that brief work, the body is a welcome addition to my old Ion.
Nice upgrade for the original Ions. 
